Appearance of antibodies against phosphotyrosine and tyrosine phosphorylation of lymphocyte proteins in human T cell leukemia virus type-I infection.

Antibodies reactive with O-phosphotyrosine (Ptyr) were detected in all of 56 patients with adult T cell leukemia (ATL) with high titers ranging from 1:1,600 to 1:25,000 in 91% of the patients, whereas 97% of 70 healthy subjects showed titers of 1:400 or less. Ptyr-containing proteins (molecular weights of 70k, 45k and 30k) were detected in peripheral lymphocytes from patients with ATL. These proteins might be involved as antigens in the induction of such antibodies.